1. Field of the Invention
This invention relates to a stabilized benzimidazole derivative and a composition in which a benzimidazole derivative is stabilized.
2. Description of the Prior Art
There is known a physiologically active benzimidazole derivative having the formula (I): ##STR2## wherein R.sup.1 is hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, a cycloalkyl group, phenyl group or an aralkyl group, R.sup.2 is hydrogen atom or a lower alkyl group, or R.sup.1 and R.sup.2 together with the adjacent nitrogen atom form a ring, and each of R.sup.3a, R.sup.3b, R.sup.4a, R.sup.4b and R.sup.4c independently is hydrogen atom, a halogen atom, a fluoroalkyl group having 1 to 6 carbon atoms, a lower alkyl group, a lower alkoxy group, a lower alkoxycarbonyl group or an amino group.
The benzimidazole derivative of the formula (I) shows a prominent inhibitory action on secretion of gastric acid as is described in GB 2,161,160A and GB 2,163,747A (corresponding to DE 3,531,487A1). Moreover, some benzimidazole derivatives of the formula (I) can be employed as cytoprotective agents for gastrointestinal tract.